Calling it a “people’s public hearing,” the Sierra Club and other environmental groups Thursday night called on the Tennessee Valley Authority to end its reliance on coal as a source of power.

More than 200 people attended the event at Nashville’s Looby Theater. It was aimed at gathering input about TVA’s plan to spend $1 billion upgrading the Gallatin Fossil Plant with new pollution controls.

TVA did not hold a formal public hearing after it released a draft environmental report on the upgrades late last year.

Many of those attending dressed in yellow “Beyond Coal” T-shirts that the Sierra Club provided and urged TVA instead to invest in conservation and energy efficiency programs.